Silyajstus phillips thompson asfd philip joles



mmoael.) S. P. THOMPSON 8v P. JOLIN.

TELEPHONE TRANSMITTBR. No. 3395499. Patented Apr. 6, 1886.

SILVANUS PHILLIPS THOMPSON AND PHILIP JOLIE, OF BRISTOL, COUNTY OF GLOUCESTER, ENG LAND.

TELEPHONE-TRANSMITTER.

SPECEFICATION forming part of Letters Patent No. 339,499, dated April 6, 3.886,

Application tiled November 22, 1584.

Serial No. 148,605. (No model.) Patented in England June 3, 1854, No. 8,524, and in Germany November 28,1884, Xo. 32,278.

To @ZZ whom it may concern:

Beit known that We, Similares PI-IILLIrs THOMPSON and PHILIP Joigny, subjects o the Queen oi' Great Britain, both residing in the city of Bristol, and county ol' Gloucester, Eugland, have invented certain new and useful Improvements in Transmitters for Electric Telephones, (for which we have received Let ters Patent of Great Britain, No.S,52-il,of1884,) of which the following is a specification.

In most of the forms oi' telephonie transmitters hitherto in use one or both of the electrodes have been att-ached either to springs or to a tympanum or diaphragm, or to some attachment capable of taking up rhythmieal vi brations imparted by means of a tympanum or diaphragm. Ourinvention differs essentially from these in that the movable portion of the electrodes or conductors is constructed in the forni of a valve. For example, one of the electrodes or contact-pieces may constitute the valve-seat and the other the ball, plug, ilap, or other movable portion ofthe valve, resting under normal conditions upon its seat, and so arranged that atmospheric vi bratious or sound- Waves produced bythe human voice or otherwise tend lo raise or open the valve by automatically/'lifting the ball, plug, flap, or other movable portion more or less completely from its seat and letting it fall again.

1n a Patentissued May20, 1884, No. 299,073, there is described an apparatus operated in somewhat the manner described above; but in this several contact balls or spheres rest against the confronting edges of two sections of a diaphragm. By ourinvention only one sphere is required, and this, instead of resting against the edges oi' a diaphragm, is supported directly above the end oi' the speaking-tube by contactpins and receives the full force ofthe air-Waves.

The accompanying drawings represent one form ol' apparatus embodying our invention, in which Figure 1 is a vertical transverse seotion of the apparatus, and Fig. 2 is a plan view of one portion of the same.

Referring to Fig. l, A is abox or case,which serves to support or protect the working parts of the apparatus. Y

B is a cylindrical block, preferably of Wood or other non conducting material, which is 5o provided about midway of its length with a projecting flange, I1. Thelower portion of the cylindrical block B passes, without touching, through a circular aperture, a, formed in the bottom of the box or case A. The block B is supported and maintained in its position by two annular rings, O and C', of india-rubber orotlierequivalent dampening 1naterial,\vhich encircle said block and prevent vibration of the box or ease from affecting the working 6o parts.

D is a hollow tube, of brass or other suitable metal, which is situated Within a cylindrical cavity, b', extending in a vertical direction axially through the block B. The lower por tion of the cylindrical cavity b is of such diameter' that the met-allie tube D fits closely Within it, as shown in Fig. 1; but the upper portion el' the same cavity is preferably of greater diameter, so as to leave an annular 7o air-space between the tube D and the inner surface of the block P. The tube D is of such length that its upper end is somewhat below the upper end ofthe block B, which eneircles it, as shown in Fig. 1.

Above the upper end ofthe tube D there is placed a valve, E, which valve is preferably a hollow spherical mass of some suitable metal or metalloid or alloy, preferably of phosphor bronze, silicium bronze, selenium bronze, or So sulphur bronze.

Three pins, F, F', and F2, are inserted in the upper port-ion of the block B, and bear against the sphere or ball E at three equidistantpoints in a horizontal plane, cutting the said sphere at a point below its center. Two of these pins, F and F', are preferably tipped with gold, platinum, iridium, or other suitable metal or conducting material; but such provision is not necessary in ease the third 9o pin, F2, is not used as an electrode, in which ease it does not forni a portion of the electric circuit, as hereinafter explained. These contact-pins may be made,if preferred,adjnstable, by having a screw-thread cut upon them.

Upon the lower end of the block B is screwed or otherwise secured an annular cap, G, provided with a central opening, g, into which is inserted the end-of a speaking-tube, H, which may be provided with a suitable mouth-piece, 7l.. The tube H may be either rigid or flexible, and may be of any convenient length.

As it is desirable to maintain the apparatus hereinbefore described in an upright position, and to have the speaking-tube enter from beneath, it is preferable to construct it With a,

curve similar to that shown in Fig. l, for greater convenience of use.

rlhe electric circuit enters at the bindingscrew L and passes by the wire Z to the platinum-tipped contact-pin F, thence through the ball or valve E, and to the platinum-tipped contact-pin F', and thence through the wire Z to the binding-screw L.

The transmitter thus constructed may be used in the ordinary manner, it being usually preferable to include the same, together with a suitable battery, in the primary circuit of an induction-coil at the transmitting-station. The secondary circuitl of the same coil is continuous with the line extending to the distant station,at which point any suitable receivingtelephone may be included in the circuit.

In order to arrange the apparatus for operation as a telephonie transmitter, the pins F, F', and FZ should be set up against the ball E sufficiently to nearly or quite raise it from contact with the upper end of the tube D.v

The electric circuit will then uninterruptedly traverse thc ball or valve E and two of its three supports. In some cases the current enters by two of the three pins and leaves by the third pin,or vice versa. lf, now,a person speaks into the speaking-tube H, for example, the atmospheric sound-waves are conducted by said tubes through the opening G into the tube D, and thus impinge directly against the lower surface of the ball E, tending to raise it more or less from its seat or from the points of the contact-pins F and F, thereby giving rise to iluctuations or variations in the strength ofthe electric current passing therethrough, which iiuctuations, acting through the medium of a suitable telephonie receiving-instrument, reproduce in a well-known manner the soundwaves which originally acted upon the transmitting apparatus.

In our transmitter it is not essential that the valve should be entirely closed when in its normal position, and in some cases apertures may be expressly provided, in order to x prevent the valve when resting upon its seat from absolutely closing the air-passages. The sound vibrations or waves traversing the atmosphere are made to impinge upon the valve, and they may strike either upon its upper or upon its lower surface or upon both surfaces.

any non-metallic conducting substance, such as cokewhich can be made up in the shape of a clack, plug, ball, frustum of a cone, zone of a sphere, or other suitable forni for a valve of the ordinary` hind. The valve may in some cases be made of Wood or other nonconducting material, and the electrodes or contact-pieces are placed at the top or side of it, so that when the air-waves tend to open vthe valve to a greater or lesser degree the valve in turn, bythe motion which it imparts i to the electrodes or contact-pieces, tends to increase to a corresponding degree the resistance of the electric circuit, and thereby affects the quantity of electric current which flows through the electrodes.

In order to prevent undue sparking whenV strong currents are to be transmitted, several valves may be used, each consisting of a ball, plug, clack, or other suitable piece resting upon its own seat and serving as an electrodeA or as a means of actuating separate electrodes or contact-pieces. The sound-waves in this case will act simultaneously upon the several valves, which, since each of them receives a part of the current, simultaneously act upon their own part of the current and set up in it the requisite fluctuations, corresponding to the opening of the valves to a greater or lesser degree by the airwaves. y

Ve claim as our inventionl. A telephonie transmitter consisting of the combination, substantially as hereinbefore set forth, of a speaking-tube, a spherical valve partially closing the same, and one or more contact-pins supporting said valve.

2. The combination, substantially as hereinbefore set forth, with a speaking-tube, of a spherical conducting-valve, adjustable contact-pins supporting said valve at the end of said tube, and means for completing an electric circuit from said pins through said valve.

In testimony whereof we have hereunto subscribed our names this 6th day of November, A. D. 1884.

SILVANUS PHILLIPS THOMPSON. PHILIP JOLlN. l lVitnesses:

XV. M. MooRsoM, EDWARD AUGUsrINn OKEEFFE.

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